Sampat & Williams on the Effect of Gene Patents on Follow-on Innovation

Bhaven Sampat (Columbia Public Health) and Heidi Williams (MIT Econ) are two economists whose work on innovation is always worth reading. I've discussed a number of their papers before (here, here, here, here, and here), and Williams is now a certified genius. They've posted a new paper, How Do Patents Affect Follow-On Innovation? Evidence from the Human Genome, which is an important follow-up to Williams's prior work on gene patents. Here is the abstract:

We investigate whether patents on human genes have affected follow-on scientific research and product development. Using administrative data on successful and unsuccessful patent applications submitted to the US Patent and Trademark Office, we link the exact gene sequences claimed in each application with data measuring follow-on scientific research and commercial investments. Using this data, we document novel evidence of selection into patenting: patented genes appear more valuable — prior to being patented — than non-patented genes. This evidence of selection motivates two quasi-experimental approaches, both of which suggest that on average gene patents have had no effect on follow-on innovation.

Their second empirical design is particularly clever: they use the leniency of the assigned patent examiner as an instrumental variable for which patent applications are granted patents. Highly recommended.